JPH02175949A - Loom without shuttle - Google Patents

Abstract

PURPOSE: To surely capture a weft yarn flying with a compressed air nozzle with a small amount of air by using a brake comprising a zigzag passage attached to the upstream side of an aspirator provided on the side opposite to the yarn feed side and formed between an intake end and a release end. CONSTITUTION: This shuttleless loom is obtained by installing a mechanical brake 22 aligned in the axis 20 at the end on the upstream side of a fitting 17 of a pneumatic type aspirator 16 in the shuttleless loom capable of capturing a weft yarn 1 flying with a compressed air nozzle by the pneumatic type aspirator 16 aligned in the weft yarn direction on the other end of the loom. The brake 22 is provided with an intake tube 24 at the end on the upstream side and a frustoconical type release end 25 at the end on the downstream side and a slot in the transverse direction is formed in a tube 23 extending between both ends. Vanes 28 extending at right angles to the axis 20 are attached to form a zigzag passage 29. The weft yarn 1 flying from the side of the yarn feed of the loom is sucked into the intake tube 24 and braked in the zigzag passage 29.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a weaving machine in which the weft thread is inserted pneumatically, i.e. without a shuttlecock. In particular, the invention relates to a weft thread aspirator holder for such a weaving machine.

BACKGROUND OF THE INVENTION In a standard type loom, the weft yarn is drawn from a supply spool by a mechanical feeder and fed through a constant resistance mechanical brake to a nozzle. This nozzle is directed laterally through a shed formed between the upper and lower sheds of the warp threads. In this shed, the cutting comb is guided along a path formed by the teeth of a limiting comb attached to the support.

The yarn is moved across the entire width of the fabric in the weft direction by each relay nozzle spaced apart and sequentially pressurized along the shed.

In the downstream section of the fabric, the yarn is captured by an aspirator and held by the aspirator.

Such structures are described in French Patent Nos. 2,184,052, 2,448,293 and 2,526,053.

The aspirator, like the relay nozzle and the insertion nozzle, is operated by air pressure to draw suction into the transverse filament.

The aspirator is usually formed by a tube with an internal air jet aligned with and directed away from the insertion nozzle, so as to create a suction end at the suction end of the tube by a venturi or jet pump effect. It's Nishide. The downstream flow of air away from the insertion nozzle not only draws in the weft filament but also holds it under some tension as it is sucked. The function of this holder, which sequentially pressurizes the suction jets after the last nozzle of the relay nozzle so as to save compressed gas, is to position the weft thread during beating and then to hold some tension on this weft thread. be. However, this system not only wastes a significant amount of compressed gas, but also often fails to maintain sufficient tension in the weft thread. Additionally, this system relies on a relay nozzle for the retention action, thus also wasting gas.

OBJECTS OF THE INVENTION The object of the invention is therefore to provide a new weft thread holder or catcher for a loom with pneumatic weft thread insertion.

It is a further object of the invention to provide a weft thread catcher as described above which retains the weft thread reliably but uses only a small amount of air to do so.

SUMMARY OF THE INVENTION The present invention provides for pneumatically inserting weft filaments in the weft direction through a warp shed by a nozzle on one side of the warp thread 1 and aligning them in the direction from said nozzle on the other side of said shed. Used in looms where the needles are captured by a pneumatic aspirator. The present invention is arranged such that on the other side of the loom the yarn is held in mechanical contact with the aspirator immediately upstream or downstream thereof after it has been captured by the aspirator. It has mechanical brakes.

That is, according to the present invention, when a slight tension is applied to the filament on the upstream side of the brake and aspirator, the filament lightly held by the aspirator contacts the braking member and is mechanically captured by the braking member.
The amount of thread tension increases significantly. In this way a precise weaving effect is obtained.

According to the present invention, the brake includes a tube having a suction end opening toward the nozzle and a discharge end opening away from the nozzle, and a brake disposed within the tube between the respective tube ends. at least one brake member defining an extending non-straight path. The path bounded by this damping member increases in flow cross section from the suction end to the discharge end. That is, the weft filament is attracted and reliably fed along said path regardless of whether the brake is at the upstream or downstream end of the aspirator.

According to the invention, the tube has a generally uniform cross section;
There are a plurality of blades spaced apart from each other inside. These vanes constitute damping members, each of which obstructs most, but not all, of the cross-section of the tube, causing the path to be tortuous. The tube has opposite sides. Each vane extends along this path from each leg, alternating from one side thereof to the other. In fact, the upper vanes extend generally perpendicular to the tube, although they may extend at an acute angle to the tube. The vanes are spaced apart from one another along the tube at increasing intervals from the suction end to the output end so that the flow cross-section of the path increases downstream, or such that the flow cross-section of the path increases downstream.

Another construction according to the invention is to form a helical ridge on the brake member so that the path is helical. Each tube end can be aligned in direction with each other. The damping member, which can also be substantially aligned with a line corresponding to the direction of the ridges of the damping member, is shaped such that the flow cross-section of the path increases from the suction end to the discharge end. Also, each tube end is offset transversely to said direction, the direction of the suction end is directly aligned with the nozzle, the ridges are centered on a line approximately perpendicular to said direction, and the suction end is oriented tangentially to this line. The opening and the discharge end are open.

Furthermore, according to the present invention, the mechanical brake is an aspirator.
a pair of gripping members adjacent to each other; a spring biasing the gripping members toward each other; and a spring biasing the filament laterally between the gripping members after the filament is captured by the aspirator. It can be provided with guidance to The guide may be a non-straight or S-shaped guide tube with an upstream end open in said direction and a downstream end laterally offset in said direction opposite the upstream end. Each tab member is located on one side of the upstream end.

[Embodiment] An embodiment will be described with reference to the drawings. As shown in FIG. 1, a machine according to the present invention has a weft thread (1). The weft yarn (1) is drawn out from the supply spool (2) by a mechanical rotary feeder (3) and fed as a weft yarn to a nozzle (5) via a mechanical brake (4) with constant resistance. The nozzle (5) is oriented laterally through a hole formed between the upper and lower holes of the warp (6). In this shed the thread (1) is guided along a path (7) formed by the teeth of a limiting comb (8) which is attached to a support (9) together with a cutting comb (10). The yarn (1) is moved over the entire width of the fabric (11) in the weft direction by means of a relay nozzle (12).

Each relay nozzle (12) is sequentially energized at intervals along the shed in a well-known manner.

At the downstream edge of the fabric (11) the thread (1) is captured by a weft thread aspirator/holder (13).

A photoelectric detector (14) in the shed detects the presence or absence of the thread (1) and in particular controls the action of the holder (13) and stops the loom if no weft thread is fed. Detector (14)
is resting on the same support (9) as the combs (8), (10). The scissors (15) on the upstream side of the shed serve to cut the weft thread when it is struck.

All holders (13) according to the invention are equipped with an aspirator (16) provided with a suction end fitting (17), as shown in detail in FIG. The fitting (17) is connected to a pressurized gas supply source by a coupling (18) and is connected to an axis (20).
It extends as a tube (19) centered on.

The axis (20) coincides with or is parallel to the line or axis A along which the weft thread (1) is discharged by the nozzle through the shed. These parts include fittings (17) and joints (18).
), the tube (19) and the axis (20) can be configured to act in a venturi-like manner as described in the above-mentioned French Patent No. 2.526.053.

Figure 1 shows the pressure line (21) attached to the fitting (18). Air is blown into the cloth (1) from the nozzle (5).
1) on the downstream side in the axial direction with respect to the direction of movement of the thread (1).

In the first system shown in FIG.
, (20), a mechanical brake (
22) is provided. The brake (22) has at its upstream end a small-diameter suction pipe (24) aligned with the axis A and (20), and at its downstream end a conical trapezoidal joint that can be attached to a fitting (17). (25) is provided. Pipe (2
3) comprises an earthen wall (26) and a lower wall (27) with transverse slots formed therein. In each slot, axis A,
(20) are attached with vanes or partitions (28) extending orthogonally to the planes (20). Each partition (28) has a full width between the side walls of the tube (23), but has a height equal to substantially more than half, but not the entire, internal height of the tube (23). Each partition (28) is located alternately upward and downward in the upper and lower walls (26), (27), and each partition (28) forms a vertically winding passage (29) for the weft thread (1). That's what happened.

Further, the height of the partition (28) increases in the downstream direction (from the left to the right in FIG. 2), and the flow cross section of the passage (29) decreases in the downstream direction. Pipe (23), fitting (1
The entire combination of combs (8), (7) and tubes (16)
Mounting stand (32) fixed to the support (9) that supports 10)
It is supported through two legs (30) and (31).

That is, the downstream air flow generated by the venturi effect in the fitting 17) draws the weft thread (1) into the upstream end of the tube (24). The weft thread (1) then follows a zigzag path (29) via a brake (22). The contact of the weft threads (1) with the edges of each partition (28) creates a mechanical braking action that keeps the weft threads (1) under tension during the cutting of the shed. course(
The zigzag or tortuous shape of 29) allows the braking action to naturally increase when tension is created in the weft thread (1) by bringing the weft thread (1) into contact with mechanical elements on opposite sides thereof.

Figure 3 shows a mechanical brake (34) constituted by a relatively large diameter circular section tube (34) aligned with the axis A, (20〉) at the upstream end of the suction fitting of an ordinary weft thread aspirator. The weft thread aspirator is equipped with a small diameter suction tube (35) at its upstream end slightly off-center with respect to each axis
), and the downstream end is provided with a conical trapezoidal joint (36) attached to the fitting (17).The pipe (34) is provided with a spiral shaped member (37) inside. The shaped member (37) has a helical ridge (38) delimiting a helical passageway (39) which opens at its upstream end into the suction pipe (35) and at its downstream end into the trapezoidal joint (36).
have.

The downstream air flow caused by the Venturi effect in the fixture (17) causes the weft (1) to move into the tube (35).
is sucked out to the upstream end of the The weft thread (1) then passes through a brake (33) for a mechanical braking action which, by contact with the edge of the helical channel (39), holds the weft thread (1) under tension during beating in the shed. The core diameter of the spiral shaped member (37) is reduced or its ridges (38)
and/or both, such that the dimensions of the passageway (39) increase in the downstream direction.

The system of FIG. 4 differs from the system of FIG. 3 in that the axis A, (20) is offset by a distance
) and tube (34) are aligned with axis A, axis (40) perpendicular to (20) and intersecting these. Each end of the tube (34) is closed by a stopper (41), (42), and each tube (35), (17) is aligned with the axis (4).
0) in the tangential direction. i.e. weft (1) during use
is a spiral shaped member (
37) Wrap it around the heart.

5 and 6, a mechanical scissor brake (43) is provided at the upstream end of the S-shaped tube (44).The upstream end of the tube (44) is aligned with axis A. , Matata pipe (
The downstream ends of 44) are offset from each other in alignment with axis (20). The brake (43) has an axis A, (2
0) and includes a lower anvil (49). The piston (45) faces the anvil (49), and the tube (
46) and is pressed by a spring (48) which supported the stopper (50). The scissors between the piston (45) and the anvil (49) are such that when a tensile force is applied to the weft thread (1) through the aspirator/holder (13) as shown by the solid line, the weft thread (1) It occupies the position shown by , and is positioned so as to be sandwiched between the piston (45) and the tube (46). The holding action is important and the air supply to the fixture is cut off as soon as the weft thread (1) is caught. Of course, other types of scissor brakes may also be used. Once the weft thread is beaten, it can be pulled out of the brake (43).

7 and 8, a brake (51) is provided which is constructed similarly to the brake of FIG. 3, except that it is provided downstream of the fitting (17), i.e. at its outlet. However, in this case the channel (29) has an increased cross section.

Distance e between partitions (28) adjacent to each other in the direction of movement
In addition, the edge of the blade (28) and the square housing (2
3) The effect can be obtained by increasing the distance between the walls (26) and (27). It is clear that the number of vanes and the cross section of the tube may vary without departing from the scope of the invention.

Furthermore, each blade (28') can be inclined with respect to the axis (20) to enhance the braking effect.

Although the present invention has been described above in detail with reference to its embodiments, it is of course possible to make various changes and modifications to the present invention without departing from its spirit.

[Brief explanation of the drawing]

FIG. 1 is a diagrammatic perspective view of an embodiment of a loom according to the invention. 2, 3, 4 and 5 are axial sectional views of the weft aspirator/holder of the loom of the present invention. Figure 6 is V in Figure 5? 7 is a sectional view taken along line Vl-Vl of FIG. 8, which will be described later, showing a modification of the weft aspirator/holder of the present invention. FIG. FIG.

Claims (20)

[Claims] (1) inserting a weft yarn by air pressure in the weft direction through a warp shed by a nozzle on one side of this shed, and aligning said weft yarn in said weft direction on the other side of said nozzle of said shed; In a loom having a pneumatic aspirator for catching, the other loom side has a mechanical brake aligned with the pneumatic aspirator in the weft direction, and the weft is mechanically brought into contact with the weft after the weft is caught by the aspirator. A lace loom, characterized in that it includes brake means for holding the loom. (2) a tube having a suction end opening toward the nozzle in the weft direction and a discharge end opening away from the nozzle in the weft direction; The lace loom according to claim 1, further comprising: at least one braking member forming a non-straight path extending between both tube ends. (3) The lace loom according to claim 2, wherein the path formed by the braking member has a flow cross section increasing from the suction end to the discharge end. (4) a tube having a generally uniform cross-section, the tube having a plurality of spaced apart vanes constituting each damping member therein, each blocking a major portion, but not all, of the cross-section of the tube; 3. A lace loom according to claim 2, further comprising: a winding path in said tube. (5) The tube is provided with foot portions facing each other, and each vane extends from each side portion of the tube alternately from one foot portion to the other foot portion along a path within the tube. Hinoki loom. 6. A lace loom according to claim 5, wherein each vane extends generally perpendicular to the tube. (7) A lace loom according to claim 5, wherein each blade extends at an acute angle to the tube. 8. The device of claim 5, wherein the vanes are spaced apart from each other by increasing distances along the tube from the suction end to the discharge end, such that the flow cross-section of the path within the tube increases downstream. Shi loom. 9. The loom of claim 5, wherein the tube has increasing transverse dimensions from its suction end to its discharge end, such that the flow cross-section of the passage within said tube increases downstream. (10) The lace loom according to claim 2, wherein a spiral ridge is formed on the braking member so that the path has a spiral shape. 11. A lace loom according to claim 10, wherein the tube ends are aligned with each other in the weft direction, and the ridges of the damping member are substantially aligned with a line corresponding to said direction. 12. A lace loom according to claim 11, wherein the braking member is shaped such that the flow cross section of the path increases from the suction end to the discharge end. (13) Offset each tube end transversely to the weft direction, align the suction end directly with the nozzle in said direction, and center the ridges on a line approximately perpendicular to said direction. The lace loom according to claim 10, wherein the suction end and the discharge end are opened in a tangential direction to the line. (14) The lace loom according to claim 1, wherein the brake means is located between the aspirator and the nozzle in the weft direction, and the discharge end opens directly into the aspirator. (15) The lace loom according to claim 1, wherein the brake means is provided downstream from the aspirator in the weft direction, and the suction end opens into the aspirator on the upstream side in the weft direction. (16) A mechanical brake includes a pair of scissor members adjacent to an aspirator, a biasing means for biasing each of these scissors members in a direction toward each other, and the weft thread is removed after the weft thread is captured by the aspirator. 2. A lace loom according to claim 1, further comprising a biasing means for biasing in a lateral direction between said scissors members. (17) A non-straight guide in which the weft biasing means has an upstream end that opens in the weft direction and a downstream end that is offset laterally from the upstream end with respect to one side in the direction. 17. The lace loom according to claim 16, wherein each scissor member is located on one side of the upstream end. (18) The lace loom according to claim 17, wherein an S-shaped tube is used as the non-straight guide. (19) inserting the weft yarn by air pressure in the weft direction through the warp shed by a nozzle on one side of the shed, and aligning the weft yarn in the weft direction on the other side of the nozzle of the shed; A needle loom configured to be captured by a pneumatic aspirator, having a suction end opening toward a nozzle in the weft direction and a discharge end opening away from the nozzle in the weft direction, one of the two ends. a pipe connecting a pneumatic aspirator in said direction, and a non-straight path provided in said pipe extending between said pipe ends and having a flow cross-section increasing from said suction end to said output end. and at least one braking member. (20) Inserting the weft yarn in the weft direction through a warp shed by means of a nozzle on one side of the shed by pneumatic pressure, and inserting the weft yarn with an upstream end and a downstream end into the nozzle of the shed. a pair of scissor members; and biasing means for biasing each of the scissor members toward each other. and an upstream end that opens in the weft direction and a downstream end that is laterally offset from the upstream end with respect to one side in the direction, and one of the two ends is connected to both ends of a pneumatic aspirator. a non-straight guide connected to one of the upstream ends and locating each of the scissor members relative to one side of the upstream end.